Unit 8 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity Copyright © Houghton Mifflin Harcourt Publishing Company

Unit 8 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity

Copyright © Houghton Mifflin Harcourt Publishing Company


Florida Benchmarks


• SC.6.N.3.4 Identify the role of models in the context of sixth grade science benchmarks.

• SC.6.E.6.1 Describe and give examples of ways in which Earth’s surface is built up and torn down by physical and chemical weathering, erosion, and deposition.

• SC.6.E.6.2 Recognize that there are a variety of different landforms on Earth’s surface such as coastlines, dunes, rivers, mountains, glaciers, deltas, and lakes and relate these landforms as they apply to Florida.


While taking notes, keep in mind our learning goal for 8.3!


How can wind shape Earth?

When wind moves soil, sand, and rock particles, it acts as an agent of erosion.

The grinding and wearing down of rock surfaces by other rock or sand particles is abrasion.

• Rocks can become smooth and polished from abrasion.



• The removal of fine sediment by wind is called deflation.

• Desert pavement results when wind carries soil and fine sediment away from an area, leaving only rocks behind.



How can wind shape Earth?Dunes are mounds of wind-deposited sand common in

deserts and along the shores of lakes and oceans.

• Dunes usually move in the same direction the wind is blowing.

White sand dunes of Thailand

Wind is responsible for the formations of sand dunes.Copyright © Houghton Mifflin Harcourt Publishing Company


Blowing sand grains would move faster than bouncing sand grains.


Loess are thick deposits of windblown, fine-grained sediment.

• The fine-grained material in loess can be carried far away from the original source and is a valuable resource for forming good soils.




What kinds of ice shape Earth?A glacier is a large mass of moving ice that forms

by the compacting of snow by natural forces.

A glacier is formed when snow builds up, and its weight compresses the snow below into ice.

• Glaciers move downhill by gravity and cause erosion. As a glacier melts, it deposits the materials it carries.

Glacial drift is the general term for all materials carried and deposited by a glacier.


In order for this landform, glacier, to form it must be cold and more snow falls than melts.


How can gravity shape Earth?Gravity influences the movement of water and ice.

Gravity also moves rocks and soils down slope.

• Mass movement is the shifting of materials due to gravity.

• QUESTIONS????

1.What were the two types of mass movement called?

2.Which one was more dangerous?


Creep is the extremely slow movement of materials down slope.

How can gravity shape Earth?

• Rapid mass movements usually happen on steep slopes and are the most destructive.

A rockfall happens when loose rocks fall down a steep slope.

A landslide is the sudden and rapid movement of a large amount of material down slope.



How can gravity shape Earth?A mudflow is a rapid movement of a large mass of mud.

• Mudflows happen when a large amount of water mixes with soil and rock.

A sparsely vegetated mountainside is most likely where a mudflow will happen.

Fairy Stream



How can gravity shape Earth?

Deforestation, volcanic eruptions, and heavy rains can all create mudflows.

So back to our learning goal…How do wind, ice, and gravity

change Earth’s surface?

The End

Documents

Unit 8 Lesson 3 Erosion and Deposition by Wind, Ice, and Gravity Copyright © Houghton Mifflin Harcourt Publishing Company